i was under the truck checking ujoint when i push up on front end of rear drivshaft i can move the trans/ transfer case up and down pretty easy , how much much movment should there be .

 

Check the bolts for tight , are they wet with oil ? they can get soft if they are socked for long .
The drive train is mounted with rubber mounts so there would be a little movement , but not much .
You could remove bolts one at a time , & put back in with blue lock tight , after cleaning bolt & hole with brake cleaner spray .

 

mine does same thing. Bolts are all tight and truck only has 20,000 miles on it. Just the way it is designed..

 

what year is your truck lowboy?

 

bolts are tight , no oil around area just a good 3/8 of movement up and down

 

mine didnt move, maybe i didnt push hard enough?

 

truck is 04.5

 

Try to see where a gap is when you lift , could be that the rubber mount riped .

 

mount does not look ripped when you push it up you can watch it strech that much , does not look ripped not seperated from the metal plates , just seems to much to me

 

Do you get any banging when you run over rough road ?
If no banging then you should be ok .